1. Field of the Invention
This invention relates to keys for unlocking mechanical locks, and, more particularly, to a set of such keys configured to be held within a holder in a compact arrangement.
2. Background Information
The patent literature includes a number of examples of a key carrier holding the shank portions of a number of keys in a manner allowing an individual shank to be moved from a stored position within the holder to an operating position, extending outward from the holder, in which the key can be used to unlock a mechanical lock, with the holder being used as a handle to facilitate turning the key shank in the lock. In such devices, an individual key shank is slid or pivoted outward, as described, for example, in U.S. Pat. Nos. 3,147,609, 3,457,746, 5,720,211, and 5,887,468. Of these patents, U.S. Pat. No. 5,720,211 additionally describes an apparatus and method for making key shanks to be held in such a holder by removing the head portions of conventional keys.
One problem with carriers having key shanks movably attached therein arises from the fact that people change individual keys within the group of keys, as they move from one residence to another, as they replace an automobile, etc. Thus, what is needed is a compact method for carrying keys that can be readily separated for the replacement of individual keys as well as for the use of a particular key to unlock a lock.
A number of other patents describe holders for holding conventional keys in pockets formed in a planar structure. For example, U.S. Pat. No. 4,796,750 describes such a structure forming a wallet that can be folded about its center, with pickets for conventional keys on the outside, and with a currency pocket formed between overlaying layers. U.S. Pat. No. 4,946,030 describes an emergency key holder card, the size and shape of a credit card, in which keys and other incidentals, such as toothpicks, are stored. The keys may be separably retained as conventional keys within corresponding apertures of the card, or may be separably and hingedly attached to the emergency key holder card so that they may pivot into and out of the plane of the card. What is needed is a key set and holder having an ability to hold a substantially larger number of keys in a small volume.
U.S. Pat. No. 5,720,211 additionally describes a carrying case for holding a number of key shanks from which the heads have been cut away. One of such key shanks may be placed in a slot within a separate head for use to open a lock. What is needed is a compact method for storing keys that are ready to use to open a lock when they are removed from a holder.
According to a first aspect of the invention, apparatus is provided for unlocking a number of locks. The apparatus includes a set of keys, each of which includes a head and a shank, having an edge formed to unlock a lock within the number of locks, extending from the head in a first direction. Within each of the keys, the head extends in a second direction, perpendicular to the first direction, through a thickness of the head, and in a third direction, perpendicular to the first and second directions, through a width of the head, and the width of the head is substantially greater than the thickness of the head. The keys are configured to fit together in a compact arrangement, with the heads stacked against one another in the second direction and in alignment with one another in the first and third directions, and with the shanks extending in the first direction, in alignment in the second direction, and spaced apart in the third direction.
Each of the keys may also include a tab, extending from the head opposite the first direction, aligned in the third direction with the shank of the key. When the keys are placed In the compact arrangement these tabs extend in alignment in the second direction, being spaced apart in the third direction.
Preferably, within two keys of the set of keys, the shank is disposed in the third direction from a center of the head of the key, and the head is disposed in the second direction from a center of the shank. Additionally, within these two keys, the head preferably includes an interface surface facing opposite the second direction, the shank includes an interface surface facing opposite the second direction, and the key blank includes a first transition section having an interface surface extending at an acute angle between the interface surfaces of the head and the shank.
The set of keys may also include a single key having a shank aligned in the second and third directions with a center of its head, with a thickness of the shank of the single key in the second direction being substantially greater than a thickness of the head of the single key, and with the single key including a transition section, extending between the head and the shank, gradually varying in thickness between the thickness of the shank and the thickness of the head.
In accordance with the invention the keys in a set of keys are configured to fit together in a compact arrangement, with the heads of the keys being in alignment with one another in two directions and stacked against one another in another direction, and with the shanks extending essentially in alignment with one another but spaced apart along the heads.
According to another aspect of the invention, a key blank is provided for cutting to form a key within such a set of keys.
According to yet another aspect of the invention, a method is provided for making such a set of keys to form copies of a number of prototype keys.